Gifs are meant to be in the 粉丝 art section since it's something a 粉丝 has edited. The only exception would be if they were 图标 sized, but in that case they'd be moved there automatically.
Anywhere, photos, fanart, icons. Just depends on the size but it'll automatically do that for you. Like if 你 上传 a gif in 照片 but it's really small it'll just go to icons. Other than that it doesn't really matter. :)
